
3D triangles would work just like their 2D counterparts, but the points would be positioned in game world. Also there should be option to add shininess, much like in car painting.
I already can see what could be accomplished by this very simple addition: I would make a big window out of 2 semi-transparent shiny triangles. When you drive trough that window (trigger behind the window), it would shatter to tens of smaller triangles flying to ground (each animated separately) while appropriate CRASHH CLING BANG SHIRLYSHIRLY sound would play. And this is just a start ^^